From fa0d653b06cec7b3188a733dc7394e030948018e Mon Sep 17 00:00:00 2001 From: Paolo Bonzini Date: Sun, 19 Jul 2015 19:15:26 +0200 Subject: [PATCH] scsi-generic: identify AIO callbacks more clearly Functions that are not callbacks should assert that aiocb is NULL and have a SCSIGenericReq argument. AIO callbacks should assert that aiocb is not NULL. They also have an opaque argument. Reviewed-by: Fam Zheng Signed-off-by: Paolo Bonzini --- hw/scsi/scsi-generic.c | 68 ++++++++++++++++++++++++++---------------- 1 file changed, 42 insertions(+), 26 deletions(-) diff --git a/hw/scsi/scsi-generic.c b/hw/scsi/scsi-generic.c index e53470f85e..1b6350be41 100644 --- a/hw/scsi/scsi-generic.c +++ b/hw/scsi/scsi-generic.c @@ -88,12 +88,12 @@ static void scsi_free_request(SCSIRequest *req) } /* Helper function for command completion. */ -static void scsi_command_complete(void *opaque, int ret) +static void scsi_command_complete_noio(SCSIGenericReq *r, int ret) { int status; - SCSIGenericReq *r = (SCSIGenericReq *)opaque; - r->req.aiocb = NULL; + assert(r->req.aiocb == NULL); + if (r->req.io_canceled) { scsi_req_cancel_complete(&r->req); goto done; @@ -142,6 +142,15 @@ done: scsi_req_unref(&r->req); } +static void scsi_command_complete(void *opaque, int ret) +{ + SCSIGenericReq *r = (SCSIGenericReq *)opaque; + + assert(r->req.aiocb != NULL); + r->req.aiocb = NULL; + scsi_command_complete_noio(r, ret); +} + static int execute_command(BlockBackend *blk, SCSIGenericReq *r, int direction, BlockCompletionFunc *complete) @@ -172,33 +181,37 @@ static void scsi_read_complete(void * opaque, int ret) SCSIDevice *s = r->req.dev; int len; + assert(r->req.aiocb != NULL); r->req.aiocb = NULL; + if (ret || r->req.io_canceled) { - scsi_command_complete(r, ret); + scsi_command_complete_noio(r, ret); return; } + len = r->io_header.dxfer_len - r->io_header.resid; DPRINTF("Data ready tag=0x%x len=%d\n", r->req.tag, len); r->len = -1; if (len == 0) { - scsi_command_complete(r, 0); - } else { - /* Snoop READ CAPACITY output to set the blocksize. */ - if (r->req.cmd.buf[0] == READ_CAPACITY_10 && - (ldl_be_p(&r->buf[0]) != 0xffffffffU || s->max_lba == 0)) { - s->blocksize = ldl_be_p(&r->buf[4]); - s->max_lba = ldl_be_p(&r->buf[0]) & 0xffffffffULL; - } else if (r->req.cmd.buf[0] == SERVICE_ACTION_IN_16 && - (r->req.cmd.buf[1] & 31) == SAI_READ_CAPACITY_16) { - s->blocksize = ldl_be_p(&r->buf[8]); - s->max_lba = ldq_be_p(&r->buf[0]); - } - blk_set_guest_block_size(s->conf.blk, s->blocksize); - - scsi_req_data(&r->req, len); - scsi_req_unref(&r->req); + scsi_command_complete_noio(r, 0); + return; } + + /* Snoop READ CAPACITY output to set the blocksize. */ + if (r->req.cmd.buf[0] == READ_CAPACITY_10 && + (ldl_be_p(&r->buf[0]) != 0xffffffffU || s->max_lba == 0)) { + s->blocksize = ldl_be_p(&r->buf[4]); + s->max_lba = ldl_be_p(&r->buf[0]) & 0xffffffffULL; + } else if (r->req.cmd.buf[0] == SERVICE_ACTION_IN_16 && + (r->req.cmd.buf[1] & 31) == SAI_READ_CAPACITY_16) { + s->blocksize = ldl_be_p(&r->buf[8]); + s->max_lba = ldq_be_p(&r->buf[0]); + } + blk_set_guest_block_size(s->conf.blk, s->blocksize); + + scsi_req_data(&r->req, len); + scsi_req_unref(&r->req); } /* Read more data from scsi device into buffer. */ @@ -213,14 +226,14 @@ static void scsi_read_data(SCSIRequest *req) /* The request is used as the AIO opaque value, so add a ref. */ scsi_req_ref(&r->req); if (r->len == -1) { - scsi_command_complete(r, 0); + scsi_command_complete_noio(r, 0); return; } ret = execute_command(s->conf.blk, r, SG_DXFER_FROM_DEV, scsi_read_complete); if (ret < 0) { - scsi_command_complete(r, ret); + scsi_command_complete_noio(r, ret); } } @@ -230,9 +243,12 @@ static void scsi_write_complete(void * opaque, int ret) SCSIDevice *s = r->req.dev; DPRINTF("scsi_write_complete() ret = %d\n", ret); + + assert(r->req.aiocb != NULL); r->req.aiocb = NULL; + if (ret || r->req.io_canceled) { - scsi_command_complete(r, ret); + scsi_command_complete_noio(r, ret); return; } @@ -242,7 +258,7 @@ static void scsi_write_complete(void * opaque, int ret) DPRINTF("block size %d\n", s->blocksize); } - scsi_command_complete(r, ret); + scsi_command_complete_noio(r, ret); } /* Write data to a scsi device. Returns nonzero on failure. @@ -264,7 +280,7 @@ static void scsi_write_data(SCSIRequest *req) scsi_req_ref(&r->req); ret = execute_command(s->conf.blk, r, SG_DXFER_TO_DEV, scsi_write_complete); if (ret < 0) { - scsi_command_complete(r, ret); + scsi_command_complete_noio(r, ret); } } @@ -306,7 +322,7 @@ static int32_t scsi_send_command(SCSIRequest *req, uint8_t *cmd) ret = execute_command(s->conf.blk, r, SG_DXFER_NONE, scsi_command_complete); if (ret < 0) { - scsi_command_complete(r, ret); + scsi_command_complete_noio(r, ret); return 0; } return 0;